-LRB- CNN -RRB- -- Incomes ? Home prices ? New car sales ? Americans exactingly measure everything that pertains to their material well-being . But when it comes time to assess the things that matter most -- human well-being and happiness -- there we find ourselves baffled .

This week , Americans celebrate Valentine 's Day . The National Retail Federation can inform us how much Americans will spend and how that spending compares to last year and the year before that . It can tell us how much of that spending will be directed to candy , how much to cards , how much to lingerie , how much to dinners out . Specialists will inform you , if asked , about the relative size of the gay and lesbian Valentine market , how many Valentine dollars will be spent on pets , and how Valentine 's Day spending compares to Halloween and Cinco de Mayo .

But what the Valentine dollars buy ? That is a lot more obscure .

The lost art of offline dating

The statisticians can tell us that 31 million Americans live alone , and that fewer than half of American homes are shared by a husband and wife . Their data shows that the American birth rate plunged to an all-time low in 2011 , and that almost one-fifth of American women in their 40s have not had children .

But the statisticians can not tell us what we most want to know : Are these trends conducive to human flourishing ? Are we doing a better or worse job of sustaining love and family compared to other places and other times ? These questions -- the very most important of them all -- are the questions where our public discussion is most accepting of answers based on raw assertion .

`` Living alone comports with modern values . It promotes freedom , personal control and self-realization . '' That sunny assessment comes from Eric Klinenberg , author of the 2012 book , `` Going Solo . '' Maybe he 's right -- go try to prove he 's not !

The hookup culture of commitment-free sex ? It 's empowering , claims a new book excerpted in The Atlantic .

`` To put it crudely , feminist progress right now largely depends on the existence of the hookup culture . And to a surprising degree , it is women -- not men -- who are perpetuating the culture , especially in school , cannily manipulating it to make space for their success , always keeping their own ends in mind . ''

Are more children growing up in single-parent households ? That 's a good thing , asserts journalism professor Katie Roiphe in a New York Times op-ed .

The upside of online dating : Always a funny story to tell

`` If you think that being married ensures a good life for your children you need only enter a bookstore and open any novel , or go to the theater and watch practically any play , or have dinner with nearly anyone you know . Suffering is everywhere , and married parents , even happily married parents , raise screwed-up or alcoholic or lost children , just as single parents raise strong , healthy ones , '' Roiphe writes .

If we were reading about running-shoe production , or the relative costs of different sources of electricity , or the merits of different mobile phones , we 'd want facts and proof . But when it comes to the things that matter most , proof is difficult and our feelings are strong .

How technology has changed romance

`` People do n't actually read newspapers , '' quipped the great student of mass media , Marshall McLuhan . `` They slip into them like a warm bath . ''

We want to hear that Facebook can substitute for the marriages we do n't form , and that friends and pets provide more gratification than the children we do n't have .

We want to believe that we can shed sexual partners without a pang and attract new ones at every age of life .

And in our dynamic consumer economy , there is always a provider who will deliver what we want . Who will say that they are wrong ?

The opinions expressed in this commentary are solely those of David Frum .

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David Frum says we lack real evidence on the impact of living alone

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Is the dropping birth rate a good or a bad thing , he asks

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Frum : Is a new book right about the hookup culture being empowering ?

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He says we want to believe in life without traditional attachments , but is it best ?